Are you talking of a sectional door, panels hinged together, rolls up on a track? or a roll up door made of interlocking strips, or corrugated sheet, one brand of which is the "Overhead Door Company"?
In any case, you are better off buying a door locally if you can, the shipping will eat up any savings.
I went thru the experience of having doors installed. First outfit (very reputable) gave me an outlandish quote, but only after I had pleaded and begged several times for them to come out and give me the quote, and before the guy ever came out, he told me that "I couldn't afford it" referring to a sectional garage door 12w x 14h with five sections of glass in it. They guy had no idea what I could or couldn't afford, but was way high on his quote. (Amarr Door). A local fellow (nice but a country bumpkin for sure) gave me a reasonable quote on a Windsor brand door with five sections of glass (he originally quoted for three sections of glass, again thinking "I couldn't afford it" and I insisted on five sections). Poor guy wanted to weld the track to the door jams (metal building) and after seeing his welding and the welder was messed up anyhow (gas engine not running right), I insisted on bolting the tracks on, but had to show him how to do most of the install. I don't think he had ever installed a door this big before. I hadn't but certainly could figure it out, he couldn't.
Charles